🍒 [AArch64] Treat COPY between cross-register banks as expensive #11889
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…167661) The motivation is to allow passes such as MachineLICM to hoist trivial FMOV instructions out of loops, where previously it didn't do so even when the RHS is a constant. On most architectures, these expensive move instructions have a latency of 2-6 cycles, and certainly not cheap as a 0-1 cycle move.
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The motivation is to allow passes such as MachineLICM to hoist trivial FMOV instructions out of loops, where previously it didn't do so even when the RHS is a constant.
On most architectures, these expensive move instructions have a latency of 2-6 cycles, and certainly not cheap as a 0-1 cycle move.